Niels Kjærgaard received his PhD in 2001 from Aarhus University, Denmark.
We are presently developing a novel collider to perform high precision atomic physics measurements. This research is supported for three years by the Marsden Fund, selected in the 2011 round as one of 5 projects funded across Physics, Chemistry, and Biochemistry in New Zealand. As the high-energy colliders used in particle physics like the LHC at CERN, our apparatus will smash together bunches of atoms and analyze the spatial distribution of the scattered debris. However, our collider will operate in a regime of extreme contrast: it will use samples of atoms at nano-Kelvin temperatures accelerated to pedestrian velocities of up to a meter per second. The full execution of this collider utilizes a collaboration with theorists who have developed state-of-the-art calculations to extract key information from the experimental scattering patterns.
Deb, A. B., & Kjærgaard, N. (2021). Observation of Pauli blocking in light scattering from quantum degenerate fermions. Science, 374(6570), 972-975. doi: 10.1126/science.abh3470
Journal - Research Article
Chilcott, M., Thomas, R., & Kjærgaard, N. (2021). Experimental observation of the avoided crossing of two S-matrix resonance poles in an ultracold atom collider. Physical Review Research, 3(3), 033209. doi: 10.1103/PhysRevResearch.3.033209
Journal - Research Article
Otto, J. S., Hunter, M. K., Kjærgaard, N., & Deb, A. B. (2021). Data capacity scaling of a distributed Rydberg atomic receiver array. Journal of Applied Physics, 129(15), 154503. doi: 10.1063/5.0048415
Journal - Research Article
Thomas, R., Otto, J. S., Chilcott, M., Deb, A. B., & Kjærgaard, N. (2021). Reducing number fluctuations in an ultracold atomic sample using Faraday rotation and iterative feedback. Physical Review A, 16, 064033. doi: 10.1103/PhysRevApplied.16.064033
Journal - Research Article
Chilcott, M., & Kjærgaard, N. (2021). Low-cost wireless condition monitoring system for an ultracold atom machine [Tutorial]. Internet of Things, 13, 100345. doi: 10.1016/j.iot.2020.100345
Journal - Research Other
Kjærgaard, N. (2021). Effects of quantum mechanical identity in particle scattering: Experimental observations (and lack thereof). Journal of the Royal Society of New Zealand, 51(3-4), 489-512. doi: 10.1080/03036758.2021.1969957
Journal - Research Other
Kjærgaard, N., & Schumayer, D. (2021). No cleverness: Just greatness. Journal of the Royal Society of New Zealand, 51(3-4), 409-414. doi: 10.1080/03036758.2021.1982730
Journal - Research Other
Deb, A. B., Chung, J., & Kjærgaard, N. (2020). Dispersive detection of atomic ensembles in the presence of strong lensing. New Journal of Physics, 22, 073017. doi: 10.1088/1367-2630/ab9553
Journal - Research Article
Otto, J. S., Kjærgaard, N., & Deb, A. B. (2020). Strong zero-field Förster resonances in K-Rb Rydberg systems. Physical Review Research, 2(3), 033474. doi: 10.1103/PhysRevResearch.2.033474
Journal - Research Article
Thomas, R., & Kjærgaard, N. (2020). A digital feedback controller for stabilizing large electric currents to the ppm level for Feshbach resonance studies. Review of Scientific Instruments, 91(3), 034705. doi: 10.1063/1.5128935
Journal - Research Article
Sawyer, B. J., Chilcott, M., Thomas, R., Deb, A. B., & Kjærgaard, N. (2019). Deterministic quantum state transfer of atoms in a random magnetic field. European Physical Journal D, 73(8), 160. doi: 10.1140/epjd/e2019-90541-2
Journal - Research Article
Thomas, R., Chilcott, M., Tiesinga, E., Deb, A. B., & Kjærgaard, N. (2018). Observation of bound state self-interaction in a nano-eV atom collider. Nature Communications, 9, 4895. doi: 10.1038/s41467-018-07375-8
Journal - Research Article
Chisholm, C. S., Thomas, R., Deb, A. B., & Kjærgaard, N. (2018). A three-dimensional steerable optical tweezer system for ultracold atoms. Review of Scientific Instruments, 89, 103105. doi: 10.1063/1.5041481
Journal - Research Article
Deb, A. B., & Kjærgaard, N. (2018). Radio-over-fiber using an optical antenna based on Rydberg states of atoms. Applied Physics Letters, 112(21), 211106. doi: 10.1063/1.5031033
Journal - Research Article
Horvath, M. S. J., Thomas, R., Tiesinga, E., Deb, A. B., & Kjærgaard, N. (2017). Above-threshold scattering about a Feshbach resonance for ultracold atoms in an optical collider. Nature Communications, 8, 452. doi: 10.1038/s41467-017-00458-y
Journal - Research Article
Langbecker, M., Noaman, M., Kjærgaard, N., Benabid, F., & Windpassinger, P. (2017). Rydberg excitation of cold atoms inside a hollow-core fiber. Physical Review A, 96(4), 041402(R). doi: 10.1103/PhysRevA.96.041402
Journal - Research Article
Sawyer, B. J., Horvath, M. S. J., Tiesinga, E., Deb, A. B., & Kjærgaard, N. (2017). Dispersive optical detection of magnetic Feshbach resonances in ultracold gases. Physical Review A, 96(2), 022705. doi: 10.1103/PhysRevA.96.022705
Journal - Research Article
Thomas, R., Roberts, K. O., Tiesinga, E., Wade, A. C. J., Blakie, P. B., Deb, A. B., & Kjærgaard, N. (2016). Multiple scattering dynamics of fermions at an isolated p-wave resonance. Nature Communications, 7, 12069. doi: 10.1038/ncomms12069
Journal - Research Article
De Chiara, G., Kjaergaard, N., Mathey, L., & Windpassinger, P. (2016). 20 years of Bose-Einstein condensates: Current trends and applications of ultracold quantum gases. Journal of Modern Optics, 63(18), 1743. doi: 10.1080/09500340.2016.1201915
Journal - Research Other
Deb, A. B., McKellar, T., & Kjærgaard, N. (2014). Optical runaway evaporation for the parallel production of multiple Bose-Einstein condensates. Physical Review A, 90(5), 051401(R). doi: 10.1103/PhysRevA.90.051401
Journal - Research Article
Roberts, K. O., McKellar, T., Fekete, J., Rakonjac, A., Deb, A. B., & Kjærgaard, N. (2014). Steerable optical tweezers for ultracold atom studies. Optics Letters, 39(7), 2012-2015. doi: 10.1364/OL.39.002012
Journal - Research Article
Deb, A. B., Sawyer, B. J., & Kjærgaard, N. (2013). Dispersive probing of driven pseudospin dynamics in a gradient field. Physical Review A, 88(6), 063607.
Journal - Research Article
Rakonjac, A., Roberts, K. O., Deb, A. B., & Kjærgaard, N. (2013). Note: Computer controlled rotation mount for large diameter optics. Review of Scientific Instruments, 84, 026107. doi: 10.1063/1.4791796
Journal - Research Article
Deb, A. B., Rakonjac, A., & Kjærgaard, N. (2012). Versatile laser system for experiments with cold atomic gases. Journal of the Optical Society of America B, 29(11), 3109-3113. doi: 10.1364/josab.29.003109
Journal - Research Article
Rakonjac, A., Deb, A. B., Hoinka, S., Hudson, D., Sawyer, B. J., & Kjærgaard, N. (2012). Laser based accelerator for ultracold atoms. Optics Letters, 37(6), 1085-1087. doi: 10.1364/OL.37.001085
Journal - Research Article
Sawyer, B. J., Deb, A. B., McKellar, T., & Kjærgaard, N. (2012). Reducing number fluctuations of ultracold atomic gases via dispersive interrogation. Physical Review A, 86(6), 065401. doi: 10.1103/PhysRevA.86.065401
Journal - Research Article
Louchet-Chauvet, A., Appel, J., Renema, J. J., Oblak, D., Kjaergaard, N., & Polzik, E. S. (2010). Entanglement-assisted atomic clock beyond the projection noise limit. New Journal of Physics, 12. doi: 10.1088/1367-2630/12/6/065032
Journal - Research Article
Appel, J., Windpassinger, P. J., Oblak, D., Hoff, U. B., Kjærgaard, N., & Polzik, E. S. (2009). Mesoscopic atomic entanglement for precision measurements beyond the standard quantum limit. PNAS, 106(27), 10960-10965. doi: 10.1073/pnas.0901550106
Journal - Research Article
Windpassinger, P. J., Kubasik, M., Koschorreck, M., Boisen, A., Kjærgaard, N., Polzik, E. S., & Müller, J. H. (2009). Ultra low-noise differential ac-coupled photodetector for sensitive pulse detection applications. Measurement Science & Technology, 20(5). doi: 10.1088/0957-0233/20/5/055301
Journal - Research Article
Windpassinger, P. J., Oblak, D., Hoff, U. B., Louchet, A., Appel, J., Kjærgaard, N., & Polzik, E. S. (2009). Squeezing of atomic quantum projection noise. Journal of Modern Optics, 56(18-19), 1993-1998. doi: 10.1080/09500340903033682
Journal - Research Article
Oblak, D., Appel, J., Windpassinger, P. J., Hoff, U. B., Kjærgaard, N., & Polzik, E. S. (2008). Echo spectroscopy of atomic dynamics in a Gaussian trap via phase imprints. European Physical Journal D, 50(1), 67-73. doi: 10.1140/epjd/e2008-00192-1
Journal - Research Article
Windpassinger, P. J., Oblak, D., Hoff, U. B., Appel, J., Kjærgaard, N., & Polzik, E. S. (2008). Inhomogeneous light shift effects on atomic quantum state evolution in non-destructive measurements. New Journal of Physics, 10. doi: 10.1088/1367-2630/10/5/053032
Journal - Research Article
Windpassinger, P. J., Oblak, D., Petrov, P. G., Kubasik, M., Saffman, M., Garrido Alzar, C. L., … Kjærgaard, N., & Polzik, E. S. (2008). Nondestructive probing of Rabi oscillations on the Cesium clock transition near the standard quantum limit. Physical Review Letters, 100(10), 103601. doi: 10.1103/PhysRevLett.100.103601
Journal - Research Article
Mellish, A. S., Kjærgaard, N., Julienne, P. S., & Wilson, A. C. (2007). Quantum scattering of distinguishable bosons using an ultracold-atom collider. Physical Review A, 75, 020701(R). doi: 10.1103/PhysRevA.75.020701
Journal - Research Article
Petrov, P. G., Oblak, D., Garrido Alzar, C. L., Kjærgaard, N., & Polzik, E. S. (2007). Nondestructive interferometric characterization of an optical dipole trap. Physical Review A, 75(3), 033803. doi: 10.1103/PhysRevA.75.033803
Journal - Research Article
Kjaergaard, N., Mellish, A. S., & Wilson, A. C. (2004). Differential scattering measurements from a collider for ultracold atoms. New Journal of Physics, 6. Retrieved from http://www.njp.org/
Journal - Research Article
Thomas, N. R., Kjaergaard, N., Julienne, P. S., & Wilson, A. C. (2004). Imaging of s and d partial-wave interference in quantum scattering of identical bosonic atoms. Physical Review Letters, 93(17), 173201-1-173201-4.
Journal - Research Article
Kjaergaard, N., & Drewsen, M. (2003). Observation of a structural transition for Coulomb crystals in a linear Paul trap. Physical Review Letters, 91(9), 095002. doi: 10.1103/PhysRevLett.91.095002
Journal - Research Article
Kjaergaard, N., & Drewsen, M. (2001). Crystalline beam emulations in a pulse-excited linear paul trap. Physics of Plasmas, 8(4), 1371-1375.
Journal - Research Article
Kjaergaard, N., Aggerholm, S., Bowe, P., Hornekaer, L., Madsen, N., Nielsen, J. S., … Hangst, J. S. (2000). Recent results from laser cooling experiments in ASTRID: Real-Time imaging of ion beams. Nuclear Instruments & Methods in Physics Research Section A, 441, 196.
Journal - Research Article
Kjaergaard, N., Hornekaer, L., Thommesen, A. M., Videsen, Z., & Drewsen, M. (2000). Isotope selective loading of an ion trap using resonance-enhanced two-photon ionization. Applied Physics B, 71, 207.
Journal - Research Article
Madsen, D. M., Balslev, S., Drewsen, M., Kjaergaard, N., Videsen, Z., & Thomsen, J. (2000). Measurements on photo-ionization of 3s3p1P1 Mg atoms. Journal of Physics B, 33, 4981.
Journal - Research Article
Madsen, N., Bowe, P., Drewsen, M., Hornekaer, L., Kjaergaard, N., Labrador, A., … Hangst, J. S. (2000). Density distribution in laser-cooled bunch beans. Nuclear Instruments & Methods in Physics Research Section A, 441, 203.
Journal - Research Article
Madsen, N., Bowe, P., Drewsen, M., Hornekaer, L. H., Kjaergaard, N., & et al (1999). Density limitations in a stored laser-cooled ion beam. Physical Review Letters, 83(21), 4301.
Journal - Research Article
